I believe I'm raising this issue from the dead...
however, I own a D200 for more than 10 years. I was not using it much recently and it sat in the closet for quite some time (I believe at least more than a year...).
when I tried to turn it on (after charging my two batteries - one was a Nikon original), it showed me a flashing dead battery (with both batteries.
I ordered two new batteries and new charger and it remained the same.
I looked at forums where they suggest to clean the battery terminals, lens terminals in both the lens and the body - and still nothing.
I was able to hack the DC-IN and connected a 12V power supply and was able to activate the camera. it flashes "ERR" + "low battery icon" and I was not able to actuate the mirror.
still, I was able to see the FW version which was A1.01 and B1.01. I was able to upgrade to A2.01 and B2.01 (as I was reading that there was something in the past which was related to the FW version... and still I cannot turn on using the batteries. I keep checking them with the voltmeter that hey have enough power.
I'm running out of ideas... does anyone have anything new to suggest? could it be that some internal circuit just burned?
appreciate any thoughts...